Measuring sensing devices of this type are used everywhere where the rotary behavior of two construction parts turning with respect to one another is to be determined and there is to be delivered a signal corresponding to the relative rotation. In order to obtain as strong as possible an output signal it is necessary to make the space between the pole shoe of the stator and the rotor very close.
It is a known practice to apply to the pole shoe a plastic layer which in the assembling of process of the stator acts as a spacer disk between rotor and stator, but which, upon setting the measuring sensing device in operation is shaved off from the rotor (which consists of a gear disk), so that an air gap is formed between the pole shoe of the stator and the rotor. Through the shaving off of the plastic layer, however, abrasion particles can foul the measuring sensing arrangements and render it incapable of functioning.
A further known measuring sensing device is characterized in that the stator is supported by elastic spreading or clamping bodies on the fixed construction part in such a way that through relative displacement between rotor and stator after completed adjustment of the stator to a minimimal air gap in the assembling only a shifting of the stator in the sense of an increase of the air gap is possible on overcoming a considerable frictional adhesion (DAS 2,111,499).
This measuring sensing device is disadvantageous that an exact setting of the air gap between stator and rotor is not possible, since in the assembling process, the stator and rotor have to come into engagement reciprocably, and not until setting in operation of the measuring sensing device and the turning of the rotor is the stator shifted away from the rotor by an unpredictable amount.